<!DOCTYPE HTML>
<html>

<head>
        <title></title>

        <script type="text/javascript">
        </script>

        <style type="text/css">
        </style>
</head>



<body>

        <script type="text/javascript">
        var str = "192.168.237.123";
        alert(str.replace(/\.[0-9]{1,3}$/, ".0"));
        alert(str);
        </script>
</body>



</html>

